Vacuum breaker



Aug. 20, 1940. J. P. woLFF 2,212,284

` VACUUM BREAKER Filed May 2l, 1938 4 TTORNE '5.'

Patented Aug. 2o, 1940 UNITE@ .ST

This@ OFFlCE 8 Claims.

This invention relates to vacuum breakers and particularly to that type employed in connection with plumbing iixtures to prevent back siphonage of water or any other liquids from any receptacle into a supply of potable water, the principal object being the provision of a device of this type that is simple in construction, emcient in operation and economical to produce.

Objects of the invention include the provision of a vacuum breaker of the type described that is devoid of moving parts; to provide a vacuum breaker of the type described effective in preventing back siphonage of water or any other liquid from any receptacle, vat or water closet bowl and automatically operable to relieve the supply line of' vacuum at any time it occurs; to provide a vacuum breaker so constructed and arranged as to deliver water iowing therefrom in a hollow stream and providing a constantly open adequate inta-ke located most advantageously for breaking the stream in case of reversal of pressure in the supply line; to provide a vacuum breaker so constructed and arranged as to divert the maximum pressure of water iiowing therethrough from the center of the normal stream to the outside thereof and providing a constantly open communication between the stream and the outside air; and to provide a vacuum breaker of the type described having means for diverting the flow of water thereto away from the center of the stream and delivering water therefrom in a hollow stream, together with the provision of constantly open air inlets to the stream positioned upstream from the point of iinal discharge of the cylindrical stream of wateA from the device.

Other objects of the invention include the provision of a vacuum breaker provided with a centrally disposed cone therein having its apex directed upstream with respect to the flow of water therethrough, the cone being so constructed and arranged as to cause water flowing through the vacuum breaker to be discharged therefrom in a hollow stream; the provision of a vacuum breaker having a constantly open passageway therethrough, the passageway being restricted by means of a cone-like obstruction placed therein with the apex thereof directed upstream with respect to the direction or" flow of water therethrough, the margins of the cone adjacent the base thereof cooperating with the walls of the passage to eifecta discharge in the water from the vacuum breaker in a hollow stream; and the provision of a construction as above described including means for introducing air directly into (Cl. LTL-111) the vacuum breaker at a point upstream from the base of the cone.

Further objects of the invention include the provision of a vacuum breaker having provision for separating the stream of water flowing thereinto a plurality of circularly arranged streams; the provision of a vacuum breaker of the type described including a plurality of Venturi-like passages arranged in circular formation; the provision of a construction as above described in 10 which the vacuum breaker is provided with constantly open passages connecting the interior thereof with the air exterior thereof, the passages being arranged intermediate the separate stream forming means; the provision of a vacuum 15 breaker having provisions for breaking up the iiow of water thereto into a plurality of circularly arranged streams and having means providing open communication between the interior and the exterior of the vacuum breaker between such separate streams, together with means for combining such separate streams into a tubular stream and discharging the same from the vacuum breaker; and the provision of a vacuum breaker` so constructed and arranged as to sep- 25 arate water flowing thereto into a plurality of circularly arranged streams and providing air passages between such streams together with cone-like means for receiving such streams and combining them into a single hollow cylindrical 30 stream for discharge from the vacuum breaker.

Still further objects of the invention include the provision of a novel anti-splash guard for a vacuum breaker; the provision of a novel form ofl silencing mechanism for vacuum breakers; the provision of a novel silencing mechanism for vacuum breakers also serving as a Splash guard;

and the provision of a novel means for use in connection with a vacuum breaker for concealing the air inlet passages thereof from view and at the same time serving to muie the sound of water flowing through the vacuum breaker and limiting the escape of water therefrom through the air passages.

rihe above being among the objects of the present invention the same consists in certain novel features of construction and combinations of parts to be hereinafter described with reference to the accompanying drawing, and then claimed, having the above and other objects in vlew.

In the accompanying drawing which illustrates suitable embodiments of the present invention and in which like numerals refer to like parts throughout the several different views,

A Fig. l is a side elevational view of a toilet seat to which my improved vacuum breaker is shown applied;

Fis. 2 is an enlarged fragmentary vertical sectional view taken on the line 2-2 oi Fig. l and illustrating the construction of the vacuum breaker in detail;

Figs. 3, 4 and 5 are transverse sectional views taken on the lines i1-Ji, and 5--5, respectively, of Fig 2; l

Fig. 6 is a view similar to Fig. 2 but on a smaller scale illustrating a modiiled form of construction; and,

Fig. '7 is a transverse sectional view taken on the line 'l-l of Fig. 6.

The danger of back siphonage oi contaminated water to a potable water supply through plumb- Vin the art and particularly to sanitary engineers.

Wherever there is a connection between `a supply of potable water and a relatively open body of water in any receptacle such as a vat, water closet bowl, sink, pail or the like, back siphonage or withdrawal oi the contaminated water in such receptacle into the pipe line containing the supply oi potable water i ,ay occur at any time that the pressure of waterin the supply line falls below a positive pressure unless a vacuum breaker or Vequivalent means is provided in the connection between the supply line and the receptacle. The failure or reversal of the pressure in the water supply line may occur because of a nurnber of reasons among which are the breaking of water mains or services, improperly designed or undersized water supply distributing systems in buildings and particularly taller buildings, heavy demands in extended dry periods reducing normal working pressure in city mains, nre pumping apparatus connected to a fire plug, the turning off of the water sup-ply at the oot of a pipe riser and a number of other occurrences which will readily be appreciated by those skilled in theart. Back-siphonage is likely to occur in a number of plumbing fixtures and especially in water closets which do not have to become plugged or clogged, although such plugging is not an infrequent occurrence, and the danger always exists. Many types of water closet bowls are so constructed as to provide submerged siphon jets which accelerate the flushing operation of the toilet by initiating the flow of the discharge into the waste line. in other types of plumbing fixtures the discharge end of the valve or other valve controlled tting is naturally submerged as a matter of design as for instance, in bottom inlet type bath tubs, and occurs in any case where a hose, tube or other conduit is attached to the discharge end of a faucet or nozzle and the opposite endof the hose or the like is submerged in a tank, basin, pail or other open body of water.

Such back-siphonage .may be prevented from occurring by providing means for introducing into the discharge end or the supply line adjacent such plumbing iixture air in suflcient quantity to relieve the vacuum and thus relieve the force which causes back-siphonage. A number of devices of different designs have heretofore been suggested for the purpose of brealn'ng the vacuum in a sup-ply line for the purpose above described, but as ar as l ain aware none of these have proven entirely satisiactor The bulk of the devices heretofore suggested have incorporated in them a movable valve or other device for displacei ent cfwhich is necessary for ,inatedg thus providing a construction which requires no servicing whatever and which will remain fully operative throughoutits entire life. Vacuum breakers devoid of moving par-s have also been suggested heretofore but as iar as l ain aware these vacuum breakers have not proven satisfactory under all conditions of installation. For instance, in many cases, as in connection with water closets, it is desirable to place the control valve, which must necessi y be on the upstream side of the vacuum breaker, as close as possible to the bowl, and has been found that where these vacuum breakers as previously suggested are placed, for instance six inches or less from the surface the highest water level in the closet bowl, back-siphonage may still occur under some cirotunstances.

The construction provided for by the present invention is such as to permit the installation ci the vacuum breaker within a very short distance of the surface of the water in the receptacle into which itis discharged, for example, in some cases with the discharge end of the vacuum breaker substantially flush with the highest level of water the receptacle. This advantage is obtained by discharging the water from vacuum breaker in a hollow stream and so constructing the vacuum breaker as to vprovide constantly open air inlet passages of suiii- .ient capacity above the discharge end of the vacuum breakerto immediately relieve any vacuum apparent in the supply line. It has been determined that by discharging the water from the vacuum breaker in the hollow stream described the maximum pressure ot the water is diverted from the center or the stream'ilowing into the vacuum breaker to the peripheral portions of the stream and any vacuum occurring in the supply line and tending to be transferred to the receptacle through the vacuum breaker causes a collapse oi the hollow stream and consequent severance of the conanuity of the stream between the supply line and the receptacle being unobstructed path ci iicw for the air through the vacuum breaker to the supply line to relieve the vacuum therein.

Referring now to the accompanying drawing which .illustrates suitable embodiments of the present invention and iirst to the modiiication thereof illustrated in Figs. l to 5, inclusive, a typical installation of a vacuum breaker is illustrated in Fig. l in which the numeral lll indi- Cates generally a closet bowl of any suitable or conventional construction having a water sup-- ply line l2 leading thereto controlled'by a valve l e, a vacuuun breaker'indicated generally at l being interposed between the valve lll and the closet lil.

Referring now to Figs. 2 to 5, inclusive, it will be noted that the vacuum breaker` l includes a cylindrical body shell lil open at its upper end to the interior oi the valve lll and open at its lower end to the closet bowl l0. Intermediate its length the main body portion I 8 is provided with a plurality of preferably equally angularly spaced openings 2li through the walls thereof, the openings 2li preferably being of more or less streamlined formation as shown, that is, elongated axially of the body portion i8 with the upper end thereof of maximum width and being of gradually reduced width to the bottom end thereof, the upper ends being rounded oif as indicated. Each opening 2d is bounded by an inwardly projecting flange 22 extending completely around the margins thereof and projecting radially inwardly a small but material distance as compared to the diameter of the main body portion i8 as indicated.

In the top portion of the vacuum breaker is an inverted cup-shaped member 24 arranged concentrically with respect to the main body i8 and of such diameter that its side walls are inwardly spaced with. respect to the inner walls of the main body lil by a distance sufficient to bring them into substantially ush relationship with respect to the inner edges of the various flanges 22. The side walls of the cup-shaped member 2t are arranged in inter-tting relationship with respect to the upper end portions of the various flanges 22 and the lower or open end of the cup-shaped member is preferably extended downwardly below the upper ends of the openings 2li a distance preferably in the neighborhood of 25% to 33% of the length of the openings 20.

Inasmuch as no flow of water is permitted through the bottom wall of the cup-shaped member 2d. it will be appreciated from the description thus far given that the water from the valve It flowing into the vacuum breaker ld in striking the cup member 24 will be diverted to the annular chamber formed between its side walls and the inner walls of the main body i8, and in flowing downwardly through this annular chamber such now of water will be divided by the various flanges-22 into a plurality of sepak rate streams of water circularly arranged about the axis of the main body I8. In other words each stream of water will be confined between the flanges 22 at the adjacent sides of adjacent openings 2li and because of the shape of the openu ings 2li and flanges 22 the separate passages thus provided are more or less Venturi-shaped which will have the effect of increasing the speed of flow of water therethrough and thus to increase the inertia of such water so as to carry it downwardly beyond the ends of the openings 2li and eliminating any tendency of the water to flow outwardly through the openings 2li.

Arranged in the lower end of the main body lll is a cone 26 positioned with its axis coincident with the axis of the main body i8 and with its apex pointed in the direction of flow of water through the vacuum breaker toward it. Iihe base of the cone Zd is of such diameter as to provide an annular passage 2S between it and the main body portion i8 at the discharge end of the vacuum breaker, the width of the passage 28 preferably being such in proportion to the effective area of the various streams of water flowing between adjacent flanges 2i? as to combine such streams and discharge them from the vacuum breaker in a solid cylindrical tubular form.

While the cone 26 may be supported in any suitable manner from the main body it one suitable means of support is by suspension from the cup member ZLl by means of a post of any suitable cross-sectional configuration, that shown comprising a tube 35i the lower end of which receives and is secured to the apex end of the cone 2G and the upper end of which is received in and secured to a central downwardly extending collar 32 formed in the bottom of the cup member 2d. The upper end of the tube Si] may be closed if desired but inasmuch as the cone closes the lower end of the tube 3i? this is not at all necessary in order to prevent the flow of water through the bottom of the cup member Zfl.

lt will be appreciated that with the construction thus described water flowing in a solid stream into the vacuum breaker is first divided into a plurality of separate circularly arranged streams between which are formed openings providing constantly open vent passages between the interior of the vacuum breaker the outside air, and that adjacent the discharge end of the vacuum breaker the plurality of separately circularly arranged streams are joined together and their combined contents discharged as a solid tubular stream of water from the discharge end of the vacuum breaker, and that this tubular stream, because of the design, contains a relatively high amount of kinetic energy and consequently has a relatively large amount of inertia. This high inertia of the discharge stream and its tubular form permits the vacuum breaker to be positioned in relatively close relationship with respect to the level of the water in th receptacle into which the water from the vacu in breaker is discharged and yet effectively eliminates the possibility of back siphonage even though the back pressure at the discharge end of the a cuurn breaker closely approaches the pressure in the supply line. I attribute this feature of the conw struction to the fact that any vacuum in the supply line tending to siphen back any water from the receptacle through the vacuum breaker necessitates the drawing of a tubular water into the interior of the vacuum br l. i where the presence of the vacuum on the interior of the tubular s :eam will tend to collapse this column of water and tend to cause it to follow up the surface of the cone 1"he collapse of the column of water leaves the iner walls of the main body portion l5 above the lower ends of the opening 2? substantially free of offers an immediate open path of trav entering the openings il@ to the passag s the flanges satisfy and relieve the vacuum in the supply line as well as the vacuum within the vacuum breaker which would otherwise be transmitted thereto from the supply line, and consequently relieve any water in the vacuum or aker or the re ceptacle feeding therefrom from such vacuum e id placing it under atmospheric presen under which condition it will naturally seek its ow level in the receptacle below the vacuum r. In any event regardless of the i repeated tests have indicated that the Y between in such quantita"` as to amply vacuum breaker disclosed remains fully and eoinplftely teriorly thereof. It has also been found that oc- 75 casionally, where the vacuum breaker is operated under the most adverse conditions such, for instance, where it is placed unusually close to the level of the water of the receptacle supplied through it and the valve controlling the flow of water through it is actuated in quickly repeating cycles, that an occasional drop or spray of water may find its way through the openings 2t. Accordingly, in order to muiile the sound of such water and to prevent the escape of such drops or spray of water from the vacuum breaker under such conditions I preferably employ means as best disclosed in Fig. 2 to accomplish this result. This means includes an annular outwardly and upwardly curved member 34 forming a trough S5 about the main body i8. The lower end of the member 3d is sealed to the main body E3 in preferably approximate flush relationship with respect to the lower ends of the openings 2lb and it extends outwardly and upwardly therefrom. A somewhat similarly shaped shield 38, but of smaller diameter at its open end, is secured in inverted position to the main body i8 adjacent the upper end cf the openings 2t, it extending downwardly therefrom so that any water splashing out of the openings 2G in striking the same will be collected thereby and allowed to drip by gravity into the trough E56 from which it will readily drain back into the interior of the vacuum breaker through the lower ends of the openings 2d.

A second shield member di! Vof` a character somewhat similar to the shield 38 but of greater depth than the shield' and of greater diameter at its open end than the trough 3d is xed to its upper end with respect to the main body i8 and extends outwardly and downwardly therefrom in housing relation with respect to the shield 33, preferably to a position where its lower edge is at least iiush with the upper edge of the member as indicated. The shield il@ thus acts to shield the various openings 2S from the direct passage of foreign material from the outside of the vacuum breaker and prevents in the majority of cases the passage of any material from the outside of the vacuum breaker to the inside thereof through the passages 26. The arrangement of the members 3d, 38 and lill in and of themselves form a more or less maze-like passage between the interior of the vacuum breaker and the outside air which serves to entrap and muile audible sounds on the interior of the vacuum breaker in their passage through the openings 2i) to the exterior thereof. I have found, however, that this mufiling effect may be increased by filling the space between the exterior of the shield 38 and the interior of the shield @il with a mass of preferably soft fibrous material such as 42 and which may, for instance, be suitably secured in position by a suitable layer of adhesive, pitcher other suitable substance such as i4 extending between the open ends of these shields.

In Figs. 6 and 7 a modified form of construction shown which includes a hollow cylindrical body portion i3 extending between a valve It' and, for instance, a closet bowl lll. The body portion i8 in this case is provided with a plurality of axially elongated preferably equally angularly spaced openings 20 in its vwalls intermediate its end, the openings 2Q' being shown by way of illustration as rectangular in this case. The main body id immediately above the upper ends of the openings 2b is provided with a radially inwardly extending annular flange 5 in turn provided with a downwardly extending tubular sleeve collar 52.

5I concentric with the main body I8 and spaced radially outwardly with respect to the inner margins of the flange EllA a short distance as indicated. A cone 26', illustrated in this case as being relatively more acute than the cone 25 previously described, is positioned centrally of the main body I8 with its apex facing the direction of flow of water through the vacuum breaker and extending upwardly above the iiange 5i] as illustrated. The cone 26 may be supported in position in any suitable manner, the particular manner shown comprising a plurality of radially directed platelike arms 52 arranged in cross-like formation with the planes of their thickness parallel to the iiow of water through the inlet. The inner ends of the arms 52 are suitably xed to the cone 26' adjacent the apex thereof and the outer ends of the arms 52 seat on the iiange 5] and cooperate with the interior walls of the body i8 to center the cone 26 in the body. The lower end ofthe cone 26 in this case is illustrated as terminating a short distance above the lower end of the vacuum breaker and with the base of the cone being spaced from the inner walls of the main body i8' by an amount substantially corresponding with that of the construction first described and so as to form an annular discharge passage 28 corresponding with the passage 23 previously described.

In order to provide a splash trap and muiile in this construction the main body portion i8' is longitudinally interruptedby a frusto-conical member 541 arranged concentrically with respect to the main body portion i8 and with its walls converging in a downwardly direction, the small end of the member 5t being of less diameter than the body portion i3' and the upper end thereof being of greater diameter, the line of intersection of the member 5ft and the body I8' occurring immediately below the lower ends of the openings 20. The member 54 thus provides a splash trough 5@ exteriorly of the body i3' about the lower ends of the openings 2&3. A shield 5S is secured t'o the body portion i3 immediately above the upper ends of the openings ES' and its depending outer edge is outwardly spaced from the upper edge of the member 5d and extends downwardly in protecting relation with respect thereto.

With this modified form of construction the column 'of water entering the top of the vacuum breaker is constricted by the flange 5l! and the water, particularly when under a relatively high pressure, in flowing over the ledge created by the inner margin of the flange bil causes a spray which is impinged against the inner walls of the The main flow of water is allowed to proceed axially of the device through the center portion of the flange t@ between spokes 52 following down the outside of the cone 25 is gradually spread thereby into a hollow cylindrical form. The spray which is caused by the flow of water over the inner margin of the flange 5t is confined to the inside limits of the collar 52 and continues straight downwardly until it merges with the main hollowstream about the cone 26 at a point adjacent the lower end of the member 54. As in the case of the previously described device the relation of the parts is preferably such that when this body of water reaches the lower end of the coneZ it completely occupies the passage 28 between such lower end and the interior walls of the main body I3', this feature aiding in vpreventing any water fromflowing back into the interior of the vacuum breaker in case any back pressureA is developed. i

It will be understood that the construction illustrated in lligs. 6 and 7 will function in substantially the same way as the construction illustrated in the previous views upon the occurrence of a vacuum in the supply line when the valve llt is open. In other v/ords any column of water which tei is to be Withdrawn from a receptacle through one vacuum breaker is rst impeded at the lower end of the cone 2t and will tend to collapse if carried upwardly therebeyond and will thus permit free and unrestricted flow of air through the various openings E@ upwardly through the collar 52 and flange 513 into the supply line to relieve any vacuum created therein.

It will be understood that the two illustrative embodiments of the invention shown and described are but illustrative of many different designs of the invention that will be apparent to those skilled in the art once the essential features of the present invention are disclosed and, accordingly, it will be understood that formal changes may be made in the specific embodiments of the inve tion described without departing from the spirit or substance of the broad invention7 the scope of which is commensurate with the appended claims.

What l claim is: f

l. A vacuum breaker comprising, in combination, a cylindrical hollow body portion open at one end to the flow of water thereto and open t the opposite end to the flow of water therefrom, means associated interiorly of said main body portion acting to divert the normal flow of water therethrough to the outer walls of said main body portion to the exclusion of the cenportion thereof, said main body portion having an opening therein intermediate the length thereof affording constantly open communication between the interior of said main body and the hollow interior of the body of water flowing therethrough and the atmosphere exterior thereof, and means shielding said opening from 'the direct iiow of water through said main body during flow of water therethrough in a normal direction comprising inwardly directed flange means sealed to said main body portion about the margins of said opening and having free inner edge portions terminating short of the axis of said main body portion.

2. In a vacuum breaker, in combination, a hollow main body portion open at one end to the flow of water the-reto and open at the opposite end to the discharge of water therefrom, said main body portion having an opening through a wall thereof."I providing constant open communication between the interior of said vacuum breaker and th-e atmosphere exteriorly thereof, means mounted interiorly of said vacuum breaker adjacent the upper end of said opening obstructing the new of water through said main body portion centrally thereof whereby to form an air space centrally of the body of Water :flowing through said main body portion, means associated with said main body portion arranged to protect said opening from the direct flow of water flowing normally through said vacuum breaker and to communicate said air space with the atmosphere, said protecting means comprising a short tube sealed to said main body portion around said opening and having a terminating short of the axis of said main body portion, and means within said main body portion adjacent the discharge end thereof providing an annular discharge passage for Water discharged therefrom.

3. In a vacuum breaker, in combination, a hollow main body portion open to the now of 'water thereto at one end and open to the discharge of water therefrom at the opposite end, said mailbody portion having a plurality of axially elo gated openings through the walls thereof ri ing constant open communication betwec' interior and exterior of said main body portion, means arranged within said main body no: n jacent the upper ends of said openings div the flow of water into said p from the central porof and to the interior walls thereof,

Wndirie flange means associated with tion interior-ly thereof around s ci said openings adapted to separate said diverted Water into a plurality of separate streams arr nged between said openings, the er edges of said flange means being oh other and terminating in outwardly ation with respect to the axis of said only portion, and means adjacent the disf said :nain body portion forming una discharge port therefor.

vacuum breaker, in combination, a ain body portion open to the ow of water the etc at o e end and open to the discharge of Water therefrom at the opposite end, said main body portion having a plurality of axially elongated openings through the walls eef providing constant open communication or exterior of said main means arranged within said main body portion adjacent the upper ends of said openings diverting the flow of water into said body portion away from the central portion thereof and to the interior walls thereof, iiange means associated with said main body i` `ei'ioi y thereof around the margins of said openings adapted to separate said diverted water into a plurality of separate streams arranged between said openings and to communicate the space within said streams collectively with the atmosphere through said openings, radially inner edge portions of said flange means being free whereby to directly expose the inner faces of said streams to air, and means positioned interiorly of said main body portion adjacent the discharge end thereof forming an annular discharge port for said vacuum breaker, the last me--ticned means being so constructed and arranged with respect to the interior walls of said main body portion as to combine said separate streams and discharge them from said vacuum breaker in a solid tubular stream.

5. in a vacuum breaker, in combination, a hollow main body portion open to the flow of water thereto at one end and open to the discharge of water therefrom at the opposite end, said main body portion having a plurality of axially elongated openings through the walls thereof providing constant open communication between the interior and exterior of said main body portion, means arranged within said main body portion adjacent the up er ends of said openings diverting the flow of Water into said main body portion away from the central portion thereof and to the interior Walls thereof, and ange means associated with said main body portion interiorly thereof around the margins of said openings adapted to separate said diverted water into a plurality of separate streams arranged between said openings, the inner edges of said K4fiange means being free of each other whereby to provide direct contact between the inner faces of said streams and air through said opening, and said flange means being so constructed and arranged as to provide` a plurality of Venturi-like passages acting to form said separate streams. n, l

6. In a vacuum breaker, incombination, a hollow main body portion open at one end tothe flow of water theretoand open at the opposite end to the discharge of water therefrom, means for separating the water flowing into said main body portion into a plurality of circularly arranged angularly separated streams providing an air pocket between them, said main body portion having openings therethrough angularly intermediate said streams, anges fixe-d to said main body portion and extending inwardly therefrom about the margins of each of said openings and having free inner edges whereby to provide constantly open and direct communication between the interiorV of said main body portion and the pocket within the body of water flowing therethrough, and the air eXteriorly of said main body portion, and conical means arranged within said main body portion adjacent the discharge end thereof for maintaining water discharged therefrom away from the central portion thereof.

7. In a vacuum breaker, in combination, a hollow main body portion open at one end to the iiow of water thereto and open at the opposite end .to the discharge of water therefrom, means for separating the water flowing into said main body portion into a plurality of circularly arranged angularly separated streams, said main l terior of said main body portion and the body portion having openings therethrough angularly intermediate said streams providing constantly open communication between the in body of water flowing therethrough, and the air eX- teriorly of said main body portion, flange means fixed, to said main body portion around the margins of each of said openings extending inwardly therefrom and having free inner edges, and means adjacent the discharge end of said main body portion for combining said separate streams into a single stream.

, 8. 'in a vacuum breaker, in combination, a hollow main body portion open at one end to the flow of water thereto and open at the opposite end to the flow of water there-from, said main body, portion having a plurality of openings through the walls thereof, flange means fixed to the interior walls of said main body extending inwardly therefrom about the margins of each of said openings so as to form generally radially directed passages each terminating short of the center of said main body portion, said passages being open to the atmosphere exteriorly of Vsaid main body portion and opening directly to the space interiorly of said main body portion, and baffle means within said main body portion above said flange means for diverting the ow of water away from the center of said main body portion and directing its flow means only, whereby to form an air pocket under said bafe means in direct contact with said water and directly connected to the atmosphere through said passages.

JOSEPH P. WOLFF.

to between adjacent iiange 

